The present disclosure relates to user interfaces for mixing and editing media elements.
In general, a media element can refer to audio data, video data, audio/video, and other data. Example sources for media elements include audio data from a microphone or the audio circuitry of a personal computer, audio signals from a radio receiver (e.g., in form of an mp3 file), the raw audio data stream of a compact disc drive playing an audio CD, or other types of files or data streams. Audio signals encoded in the media elements can come from different sources and have different adjustable parameters. Examples of parameters of audio signals include volume, intensity, signal type (e.g., mono, stereo), stereo width, panorama, and phase.
Properties of audio data can be edited using a graphical interface containing visual representations of media elements in a timeline environment. A conventional timeline environment can provide a one dimensional linear time-based area within the interface containing the visual representations of media elements. The timeline can be divided into one or more tracks where the tracks correspond to parallel subdivisions of the timeline.
Visual representations of media elements are referred to as clips. Clips can be arranged within the timeline. Additionally, multiple clips can be arranged within one or more tracks of the timeline. In general, there are no restrictions as to the arrangement of the clips, however, multiple clips within a single track typically do not overlap.
Clips can contain references to the source material (e.g., the media element) or they can contain copies of the source material. A clip can contain multiple parameters, each of the parameters associated with a property and/or parameter of the media element.
In general, a clip can contain values for particular effect parameters in the form of one or more control points. The control points contain the values for particular effect parameters associated with a particular point in time in relation to the timeline. Such control points are generally referred to as keyframes, keyframe controls, or keyframe control points. A clip can contain one or more groups of one or more keyframes that are associated with a time index relative to a timeline. A keyframe can contain a particular value for a particular effect parameter and serves as a marker for applying those values to the clip or track at the a specified time. Therefore, each keyframe has a type and a parameter value, and a number of keyframes can be used to convey a time dependent series of parameter value changes. A group of keyframes is part of a clip and, therefore, is also associated with a media element.
The type of a keyframe can indicate specific ways in which parameter value changes are processed. Examples for keyframe types are hold-keyframes and linear, Bézier, or spline interpolation keyframes.